Maturidade sexual e relaÃÃes morfomÃtricas do caranguejo Goniopsis cruentata (Latreille, 1803) Crustacea: Brachyura: Grapsidae) do estuÃrio do Rio Jaguaribe (Aracati - CearÃ)

A espÃcie Goniopsis cruentata apresenta valor comercial relevante no nordeste brasileiro, sendo comercializada pelos catadores, que tambÃm a utilizam para a prÃpria alimentaÃÃo. A presente pesquisa teve como objetivo determinar o tamanho no qual esta espÃcie atinge a maturidade sexual e, atravÃs da anÃlise de crescimento relativo, estabelecer relaÃÃes entre as estruturas relacionadas Ãs caracterÃsticas sexuais secundÃrias e os estÃgios de desenvolvimento reprodutivo. Os padrÃes de dimorfometria sexual da espÃcie tambÃm foram avaliados. As coletas foram realizadas no estuÃrio do Rio Jaguaribe (Aracati-Ce) durante o perÃodo de outubro/2006 a setembro/2007. Os animais eram mensurados e dissecados para a retirada de fragmentos dos ovÃrios nas fÃmeas e do vaso deferente nos machos e submetidos à rotina histolÃgica padrÃo para a estimativa da maturidade. Foram adotados dois estÃgios de desenvolvimento reprodutivo (imaturo e maduro) para ambos os sexos. Para a anÃlise morfomÃtrica realizou-se o estudo de crescimento relativo em diferentes estÃgios de desenvolvimento reprodutivo para ambos os sexos e as proporÃÃes de rescimento obtidas, testadas estatisticamente. Com base na anÃlise gonadal, observou-se que o tamanho de lc (largura do cefalotÃrax) no qual 50% dos machos e das fÃmeas apresentaram-se maduros foi de 26,40 mm e 27,48 mm respectivamente. A anÃlise de crescimento indica que esta espÃcie apresenta dimorfometria sexual evidenciada atravÃs de diferenÃas nas proporÃÃes de crescimento do abdÃmen e das quelas entre machos e fÃmeas. A comparaÃÃo entre o crescimento relativo de indivÃduos imaturos e maduros permitiu constatar diferenÃas entre a proporÃÃo de crescimento apÃs o inÃcio da maturidade sexual. Estas diferenÃas foram constatadas no crescimento do abdÃmen nas fÃmeas e das quelas nos machos, podendo-se entÃo caracterizar estas diferenÃas como caracterÃsticas sexuais secundÃrias. Estes resultados indicam haver relaÃÃo entre o processo de maturaÃÃo sexual com as alteraÃÃes na proporÃÃo de crescimento de estruturas relacionadas Ãs caracterÃsticas sexuais secundÃrias, seguindo assim, o padrÃo observado para outros caranguejos Brachyura.The species Goniopsis cruentata has an important commercial value in Northeast Brazil. The objective of the present study was to determine the size in which this species reaches sexual maturity and, through the analysis of relative growth, to establish relationships between the structures related to secondary sexual characteristics and the stages of reproductive development. The patterns of sexual dimorphism of the species were also analyzed. The samples were obtained in the Jaguaribeâs river estuary (Aracati-Ce) during the period from October/2006 to September/2007. The animals were measured and dissected for the removal of fragments of the ovaries in the females and of the vas deferens in the males that were submitted to routine histological examinations. Two stages of reproductive development were adopted (immature and mature) for both sexes. For the morphometric analysis of the individuals, it was studied the relative growth in different stages of reproductive development for both sexes. The growth proportions obtained were tested statistically. Based on the gonadal analysis, it was observed that the cw size (carapace width) in which 50% of the males and females were mature, was of 26,40 mm and 27,48 mm, respectively. The growth analysis indicates that this species presents sexual dimorphism evidenced through differences, between males and females in the proportions of growth of the abdomen and of the chelipeds. The comparison between the relative growth of immature and mature individuals allowed the registration of differences in the growth proportion after the beginning of the sexual maturity. These differences were verified in the growth of the abdomen in the females and of the chelipeds in the males, and it was possible to characterize these differences as secondary sexual characteristics. These results indicate that there is a relationship between the process of sexual maturation and the modifications in the growing proportions of structures related to secondary sexual characteristics, agreeing with a pattern observed for other Brachyura